This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We are measuring the lifetime of fluorescecnce biosensors in live cells. This in colloboration with Dr. Klaus Hahn at the University of North Carolina, Chapel-Hill. The biosensors detect GTPase activation including Rac and Rho proteins.